document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=97573>Question 97573</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How do you solve this equation??<BR>\n" );
document.write( "5x-y=10<BR>\n" );
document.write( "7x-2y=11 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #71077 by </B><A HREF=/tutors/aboutme.mpl?userid=Msgenes><B>Msgenes(10)</B></A><img src=\"/images/stars/stars-05.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Msgenes><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=71077\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> There are two ways of doing this problem by elimination or substitution. I am doing the substitution. Either way you do it you will get the same answer. \r<BR>\n" );
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document.write( "5x - y = 10 <BR>\n" );
document.write( "7x - 2y = 11\r<BR>\n" );
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document.write( "We want to get y by itself using the first equation, we do this by substracting 5x on both sides.  \r<BR>\n" );
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document.write( "5x - y - 5x = -5x + 10<BR>\n" );
document.write( "-y = -5x + 10<BR>\n" );
document.write( "Now we know that y cannot be negative so we divid by -1 on both sides.\r<BR>\n" );
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document.write( "-y/-1 = -5x/-1 + 10/-1<BR>\n" );
document.write( "y = 5x - 10\r<BR>\n" );
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document.write( "Now we are ready to substitute. \r<BR>\n" );
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document.write( "7x - 2y = 11<BR>\n" );
document.write( "7x - 2(5x - 10) = 11<BR>\n" );
document.write( "7x - 10x + 20 = 11<BR>\n" );
document.write( "-3x + 20 = 11<BR>\n" );
document.write( "-3x + 20 - 20 = 11 - 20<BR>\n" );
document.write( "-3x = -9<BR>\n" );
document.write( "Now we know that x cannot be negative so we divid by -3 on both sides\r<BR>\n" );
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document.write( "-3x/-3 = -9/-3<BR>\n" );
document.write( "x = 3\r<BR>\n" );
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document.write( "Now we have to find y by substituting x for 3. <BR>\n" );
document.write( "y = 5x - 10<BR>\n" );
document.write( "y = 5(3)- 10<BR>\n" );
document.write( "y = 15 - 10<BR>\n" );
document.write( "y = 5<BR>\n" );
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document.write( "The solution is (3, 5)\r<BR>\n" );
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document.write( "To Check this we just plug the solution into the equation. <BR>\n" );
document.write( "7x - 2y =11<BR>\n" );
document.write( "7(3) - 2(5) = 11<BR>\n" );
document.write( "21 - 10 = 11<BR>\n" );
document.write( "11 = 11<BR>\n" );
document.write( "Good Luck. Hope this helps. :) </SPAN>\n" );
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